Withdrawal reactions with selective serotonin re-uptake inhibitors as reported to the WHO system.
OBJECTIVE
The present study was performed both to investigate whether there might be a difference between the selective serotonin re-uptake inhibitors, (SSRIs) with regard to the incidence of withdrawal reactions, and to describe the associated symptoms. From the WHO database, therefore, all case reports from the year of introduction for each of the SSRIs, fluoxetine, paroxetine and sertraline, were retrieved. Sales figures were obtained from Intercontinental Medical Statistics International. The reporting rates were calculated as the number of reports per million defined daily doses (DDDs) sold per year.


RESULTS
The reporting rate of withdrawal reactions for paroxetine was found to be higher than that for sertraline and fluoxetine in each of the countries selected for detailed analyses (US, UK and Australia), as well as for all 16 countries combined. Moreover, using the WHO system of organ classification, the ratio of central nervous system to psychiatric withdrawal symptoms was 1.9 and 2.1 for paroxetine and sertraline, respectively, whereas that for fluoxetine was 0.48, indicating a possible qualitative difference between the SSRIs with respect to the nature of the withdrawal syndrome.
Stahl
M M
MM
Pharmacoepidemiology Unit, Medical Products Agency (MPA), Uppsala, Sweden.
Lindquist
M
M
Pettersson
M
M
Edwards
I R
IR
Sanderson
J H
JH
Taylor
N F
NF
Fletcher
A P
AP
Schou
J S
JS
D015057:1-Naphthylamine / Q000009:adverse effects / Q000031:analogs & derivatives; D016907:Adverse Drug Reaction Reporting Systems; D005260:Female; D005473:Fluoxetine / Q000009:adverse effects; D006801:Humans; D008297:Male; D017374:Paroxetine / Q000009:adverse effects; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects*; D020280:Sertraline; D013375:Substance Withdrawal Syndrome; D014944:World Health Organization
D015057:1-Naphthylamine; D005473:Fluoxetine; D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors; D020280:Sertraline